| Measure | Value (anomaly) | Time |
Month cumul. | Record High | Record Low |
| Minimum Temperature |
10.8 °C (-3.0) |
06:17 |
15.4 °C (+1.2) |
17.7 °C (+3.9), 2010 |
8.4 °C (-5.4), 2025 |
| Maximum Temperature |
22.8 °C (+0.6) |
15:48 |
27.8 °C (+5.1) |
30.0 °C (+7.8), 2015 |
19.2 °C (-3.0), 2024 |
| Mean Temperature |
17.2 °C (-1.2) |
|
21.7 °C (+3.1) |
22.2 °C, 2015 |
15.4 °C, 2014 |
| Minimum Humidity |
36% |
15:49 |
36% |
79%, 2024 |
33%, 2015 |
| Maximum Humidity |
81% |
06:34 |
78% |
93%, 2022 |
81%, 2026 |
| Mean Humidity |
58% |
|
57% |
86%, 2021 |
58%, 2026 |
| Minimum Pressure |
1020 hPa |
00:00 |
1015 hPa |
1024 hPa, 2019 |
1004 hPa, 2024 |
| Maximum Pressure |
1026 hPa |
23:47 |
1020 hPa |
1026 hPa, 2019 |
1013 hPa, 2014 |
| Mean Pressure |
1024 hPa |
|
1018 hPa |
1025 hPa, 2019 |
1008 hPa, 2024 |
| Mean Wind Speed |
2.7 mph (-1.3) |
|
3.9 mph (-0.1) |
9.5 mph, 2016 |
1.5 mph, 2025 |
| Maximum Wind Speed |
8.6 mph |
08:06 |
12.2 mph |
19.9 mph, 2020 |
6.4 mph, 2013 |
| Maximum Gust |
12.7 mph |
08:02 |
18.6 mph |
34.6 mph, 2020 |
8.1 mph, 2013 |
| Mean Wind Direction |
ENE |
|
|
|
|
| Rainfall |
0.0 mm |
|
2.0 mm (5%) |
5.2 mm, 2013 |
|
| Maximum Hourly Rain |
n/a |
|
|
2.5, 2013 |
|
| Maximum 10-min Rain |
n/a |
|
|
1.5, 2013 |
|
| Maximum Rain Rate |
n/a |
|
|
18, 2013 |
|
| Minimum Dew Point |
5.7 °C |
18:06 |
9.3 °C |
15.7 °C, 2010 |
4.5 °C, 2014 |
| Maximum Dew Point |
9.9 °C |
00:52 |
14.6 °C |
18.1 °C, 2010 |
9.9 °C, 2026 |
| Mean Dew Point |
8.2 °C |
|
12.0 °C |
16.7 °C, 2010 |
7.7 °C, 2014 |
| Measure | Value | Time |
Month cumul. | Record High | Record Low |
| Night Minimum (21-09) |
10.8 °C |
06:18 |
15.5 °C |
17.7 °C, 2010 |
8.4 °C, 2025 |
| Day Maximum (09-21) |
22.8 °C |
15:48 |
27.8 °C |
30.0 °C, 2015 |
19.2 °C, 2024 |
| Max 10m Temp Rise |
0.7 °C |
16:53 |
0.8 °C |
1.0 °C, 2011 |
0.3 °C, 2013 |
| Max 1hr Temp Rise |
2.6 °C |
09:28 |
3.0 °C |
4.3 °C, 2011 |
1.0 °C, 2013 |
| Max 1hr Hum Rise |
9% |
21:25 |
12% |
16%, 2021 |
4%, 2024 |
| Max 10m Temp Fall |
0.6 °C |
16:30 |
0.8 °C |
0.9 °C, 2021 |
0.3 °C, 2013 |
| Max 1hr Temp Fall |
2.3 °C |
20:34 |
2.5 °C |
3.2 °C, 2021 |
0.7 °C, 2024 |
| Max 1hr Hum Fall |
11% |
09:51 |
12% |
18%, 2025 |
4%, 2013 |
| Max 10m Wind Speed |
5.9 mph |
07:48 |
8.8 mph |
15.3 mph, 2020 |
5.0 mph, 2013 |
| Minimum Feels-like |
11.0 °C |
06:12 |
17.2 °C |
22.3 °C, 2010 |
8.4 °C, 2025 |
| Maximum Feels-like |
22.8 °C |
15:43 |
30.4 °C |
33.9 °C, 2015 |
19.8 °C, 2014 |
| Mean Feels-like |
17.8 °C |
|
24.1 °C |
25.4 °C, 2015 |
15.9 °C, 2014 |
| Air-frost Hrs |
0 hrs |
|
0 hrs |
0 hrs, 2009 |
0 hrs, 2009 |
| Minimum PM2.5 |
2 |
04:32 |
2 |
2, 2026 |
0, 2021 |
| Maximum PM2.5 |
10 |
22:20 |
12 |
10, 2026 |
10, 2026 |
| Mean PM2.5 |
4 |
|
5 |
4, 2026 |
4, 2026 |
| Measure | Value (anomaly) |
Month cumul. | Record High | Record Low |
| Temperature Range |
12.0 °C (+3.6) |
12.4 °C (+3.9) |
15.2 °C (+6.8), 2015 |
3.6 °C (-4.8), 2013 |
| Humidity Range |
45% |
42% |
57%, 2015 |
11%, 2024 |
| Pressure Range |
6 hPa |
5 hPa |
11 hPa, 2010 |
2 hPa, 2019 |
| Measure | Value [% of max] |
Month cumul. | Record High | Record Low |
| Sun Hours |
12.4 [96%] | 218 hrs (163%) [74%] |
12.4 [96%], 2026 |
0 [0%], 2024 |
| Wet Hours |
0 | 5 hrs (19%) [0.9%] |
4, 2010 |
0, 2009 |
| Cloud Cover |
unknown |
| Events |
Maximum possible sunshine |
| Comments |
data is awaiting quality control from site operator |
| Extra Comments |
|
| Issues |
None known |
| Observer Absent? |
Yes - observations may be unreliable |
| Pond Temperature @ Hampstead Heath |
23.0 °C |
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